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\begin{document}
Si $f(x)=\dfrac{x-3}{x+3}$ el valor de $f(a)$ es:\medskip\newline\qquad a)
$f(a)=\dfrac{a-3}{a+3}\qquad\qquad$b) $f(a)=\dfrac{a+3}{a-3}\qquad\qquad$c)
$f(a)=1\qquad\qquad$d) $f(a)=-1$

Si $f(x)=\dfrac{x}{x+4}$ el valor de $f(a)$ es:\medskip\newline\qquad a)
$f(a)=\dfrac{a}{a+4}\qquad\qquad$b) $f(a)=\dfrac{a}{a-3}\qquad\qquad$c)
$f(a)=1\qquad\qquad$d) $f(a)=-1$

Si $f(x)=\dfrac{x^{2}-9}{x+3}$ el valor de $f(a)$ es:\medskip\newline\qquad a)
$f(a)=a-3\qquad\qquad$b) $f(a)=a+3\qquad\qquad$c) $f(a)=3-a\qquad\qquad$d)
$f(a)=1$

Si $f(x)=\dfrac{3x}{x+a}$ el valor de $f(a)$ es:\medskip\newline\qquad a)
$f(a)=\dfrac{3}{2}\qquad\qquad$b) $f(a)=\dfrac{3a}{2}\qquad\qquad$c)
$f(a)=\dfrac{3}{2a}\qquad\qquad$d) $f(a)=1$

Si $f(x)=\dfrac{x}{x+7}$ el valor de $f(a)$ es:\medskip\newline\qquad a)
$f(a)=\dfrac{a}{a+7}\qquad\qquad$b) $f(a)=\dfrac{a}{a-7}\qquad\qquad$c)
$f(a)=1\qquad\qquad$d) $f(a)=-1$

Si $f(x)=\dfrac{x^{3}}{\sqrt{x+1}}$ el valor de $f(a)$ es:\newline\qquad a)
$f(a)=\dfrac{a^{3}}{\sqrt{a+1}}$\qquad b) $f(a)=\dfrac{a}{a-1}\qquad$\qquad c)
$f(a)=0$\qquad d) $f(a)=a$

Si $f(x)=\left\vert x-3\right\vert $ el valor de $f(a)$ es:\newline\qquad a)
$f(a)=\left\vert a-3\right\vert $\qquad b) $f(a)=\left\vert a-5\right\vert
\qquad$\qquad c) $f(a)=1$\qquad d) $f(a)=0$

Si $f(x)=\dfrac{x+1}{3x+3}$ el valor de $f(a)$ es:\newline\qquad a)
$f(a)=\dfrac{a+1}{3a+3}$ \qquad b) $f(a)=1\qquad$\qquad c) $f(a)=\dfrac{a}{2}%
$\qquad d) $f(a)=a$

Si $f(x)=\dfrac{\left\vert x-5\right\vert }{x+2}$ el valor de $f(a)$
es:\newline\qquad a) $f(a)=\dfrac{\left\vert a-5\right\vert }{a+2}$\qquad b)
$f(a)=\dfrac{a-5}{a+3}\qquad$\qquad c) $f(a)=a$\qquad d) $f(a)=0$

Si $f(x)=\left\vert \dfrac{x+7}{x-3}\right\vert $ el valor de $f(a)$
es:\newline\qquad a) $f(a)=\left\vert \dfrac{a+7}{a-3}\right\vert $\qquad b)
$f(a)=a\qquad$\qquad c) $f(a)=\dfrac{a+7}{a+3}$\qquad d) $f(a)=1$

Si $f(x)=\dfrac{x^{2}+5}{x+1}$ el valor de $f(a)$ es:\newline\qquad a)
$f(a)=\dfrac{a^{2}+5}{a+1}$\qquad b) $f(a)=\dfrac{a^{2}}{2}\qquad$\qquad c)
$f(a)=a$\qquad d) $f(a)=0$

Si $f(x)=\left\vert x+2\right\vert -2x$ el valor de $f(a)$ es:\newline\qquad
a) $f(a)=\left\vert a+2\right\vert -2a$\qquad b) $f(a)=1\qquad$\qquad c)
$f(a)=a$\qquad d) $f(a)=\left\vert a+1\right\vert $

Si $f(x)=\dfrac{1}{\left\vert x+2\right\vert }-2$ el valor de $f(a)$
es:\newline\qquad a) $f(a)=\dfrac{1}{\left\vert a+2\right\vert }-2$\qquad b)
$f(a)=a\qquad$\qquad c) $f(a)=1$\qquad d) $f(a)=\dfrac{-1}{\left\vert
a+2\right\vert }$

Si $f(x)=\dfrac{3x}{2x+1}$ el valor de $f(a)$ es:\newline\qquad a)
$f(a)=\dfrac{3a}{2a+1}$\qquad b) $f(a)=0\qquad$\qquad c) $f(a)=\dfrac{a}{a+1}%
$\qquad d) $f(a)=a$

Si $f(x)=\dfrac{5x+1}{\left\vert x-5\right\vert }$ el valor de $f(a)$
es:\newline\qquad a) $f(a)=\dfrac{5a+1}{\left\vert a-5\right\vert }$\qquad b)
$f(a)=\left\vert a-2\right\vert \qquad$\qquad c) $f(a)=0$\qquad d) $f(a)=a$


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